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android – Example of code to implement a PDF reader

Posted by: admin May 14, 2020 Leave a comment

Questions:

I want to implement a PDF reader in the application that I am doing, I have found several APIs, but none of them were open source.

Does any of you guys know a good free alternative?


Slight adaptation of Dipak Keshariya’s solution made by the OP

First Class

package android.pdf.reader;

import java.io.File;
import java.io.FilenameFilter;

import net.sf.andpdf.pdfviewer.PdfViewerActivity;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class First extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        File images = Environment.getExternalStorageDirectory();
        File[] imagelist = images.listFiles(new FilenameFilter()
        {  
                public boolean accept(File dir, String name)  
                {  
                        return ((name.endsWith(".pdf")));
                }  
        }); 
        String[] pdflist = new String[imagelist.length]; 
        for(int i = 0;i<imagelist.length;i++)
        {
                pdflist[i] = imagelist[i].getName();
        }
        this.setListAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, pdflist));
    }

    protected void onListItemClick(ListView l, View v, int position, long id) 
    {
            super.onListItemClick(l, v, position, id);
            Object[] imagelist;
            String path = ((File) imagelist[(int)id]).getAbsolutePath();
            openPdfIntent(path);
    }

    private void openPdfIntent(String path) 
    {
        try
        {
          final Intent intent = new Intent(First.this, Second.class);
          intent.putExtra(PdfViewerActivity.EXTRA_PDFFILENAME, path);
          startActivity(intent);
        }
        catch (Exception e) 
        {
          e.printStackTrace();
        }
    }

}

Secod Class

package android.pdf.reader;

import net.sf.andpdf.pdfviewer.PdfViewerActivity;
import android.os.Bundle;

public class Second extends PdfViewerActivity 
{

@Override
public void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
}

public int getPreviousPageImageResource() {
    return R.drawable.left_arrow;
}

public int getNextPageImageResource() {
    return R.drawable.right_arrow;
}

public int getZoomInImageResource() {
    return R.drawable.zoom_in;
}

public int getZoomOutImageResource() {
    return R.drawable.zoom_out;
}

public int getPdfPasswordLayoutResource() {
    return R.layout.pdf_file_password;
}

public int getPdfPageNumberResource() {
    return R.layout.dialog_pagenumber;
}

public int getPdfPasswordEditField() {
    return R.id.etPassword;
}

public int getPdfPasswordOkButton() {
    return R.id.btOK;
}

public int getPdfPasswordExitButton() {
    return R.id.btExit;
}

public int getPdfPageNumberEditField() {
    return R.id.pagenum_edit;
}
}

Thanks.

How to&Answers:

Use below code for that.

First.java

public class First extends ListActivity {

    String[] pdflist;
    File[] imagelist;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.main);

        File images = Environment.getExternalStorageDirectory();
        imagelist = images.listFiles(new FilenameFilter() {
            public boolean accept(File dir, String name) {
                return ((name.endsWith(".pdf")));
            }
        });
        pdflist = new String[imagelist.length];
        for (int i = 0; i < imagelist.length; i++) {
            pdflist[i] = imagelist[i].getName();
        }
        this.setListAdapter(new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, pdflist));
    }

    protected void onListItemClick(ListView l, View v, int position, long id) {
        super.onListItemClick(l, v, position, id);
        String path = imagelist[(int) id].getAbsolutePath();
        openPdfIntent(path);
    }

    private void openPdfIntent(String path) {
        try {
            final Intent intent = new Intent(First.this, Second.class);
            intent.putExtra(PdfViewerActivity.EXTRA_PDFFILENAME, path);
            startActivity(intent);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Second.java

public class Second extends PdfViewerActivity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
    }

    public int getPreviousPageImageResource() {
        return R.drawable.left_arrow;
    }

    public int getNextPageImageResource() {
        return R.drawable.right_arrow;
    }

    public int getZoomInImageResource() {
        return R.drawable.zoom_in;
    }

    public int getZoomOutImageResource() {
        return R.drawable.zoom_out;
    }

    public int getPdfPasswordLayoutResource() {
        return R.layout.pdf_file_password;
    }

    public int getPdfPageNumberResource() {
        return R.layout.dialog_pagenumber;
    }

    public int getPdfPasswordEditField() {
        return R.id.etPassword;
    }

    public int getPdfPasswordOkButton() {
        return R.id.btOK;
    }

    public int getPdfPasswordExitButton() {
        return R.id.btExit;
    }

    public int getPdfPageNumberEditField() {
        return R.id.pagenum_edit;
    }
}

And declared both activities into your manifest file.

Answer:

There is a very good post about this on SO. In particular check out the answer given by Commons.Ware, it answers your question.

Following your comments I have added the links here from the SO post I mentioned above (source for projects you could not find):

So “checkout” or clone the repositories to your local file system to browse the code.
As I mentioned in my comment check the licence of each library before you go any further to see if what you can and cannot do with the code.

Answer:

This one works for me.

1) Add PdfViewer.jar into your project’s build path

2) Copy the following drawable resources from PdfViewer/res/drawable into YourProject/res/drawable left_arrow.png right_arrow.png zoom_in.png zoom_out.png

3) Copy the following layout resources from PdfViewer/res/layout into YourProject/res/layout dialog_pagenumber.xml pdf_file_password.xml

4) Derive your PDF activity from net.sf.andpdf.pdfviewer.PdfViewerActivity

5) Using the default drawables and layouts:

public int getPreviousPageImageResource() { return R.drawable.left_arrow; }

public int getNextPageImageResource() { return R.drawable.right_arrow; }

public int getZoomInImageResource() { return R.drawable.zoom_in; }

public int getZoomOutImageResource() { return R.drawable.zoom_out; }

public int getPdfPasswordLayoutResource() { return R.layout.pdf_file_password; }

public int getPdfPageNumberResource() { return R.layout.dialog_pagenumber; }

public int getPdfPasswordEditField() { return R.id.etPassword; }

public int getPdfPasswordOkButton() { return R.id.btOK; }

public int getPdfPasswordExitButton() { return R.id.btExit; }

public int getPdfPageNumberEditField() { return R.id.pagenum_edit; }
enter code here

6) Invoke your PdfViewActivity derived with the following code:

Intent intent = new Intent(this, YourPdfViewerActivity.class);

intent.putExtra(PdfViewerActivity.EXTRA_PDFFILENAME, "PATH TO PDF GOES HERE");

startActivity(intent);

And you can download the source code from this link. LINK

Hope this helps 🙂